Verbs

Verbs have been extensively studied in language disorders both at the lexical and (morpho)syntactic level because of their centrality to sentence structure and communication as well as their relevance to bound morphology. A number of morphosyntactic categories are instantiated in verb morphology, including tense, aspect, mood, voice, and subject -verb agreement. Tense and Mood are closely related to time reference and modality, respectively, which are both semantic categories. This entry examines the verb with a particular focus on the morphosyntactic and semantic categories and their relative preservation or impairment in impaired adult language (in particular, agrammatic aphasia, Alzheimer’s disease [AD], and primary progressive aphasia [PPA]). This entry begins with brief definitions of these terms and presents each within the context of language disorders.